CHEM 121 FINAL EXAM QUESTIONS WITH CORRECT
ANSWERS
ionization energy✔✔amount of energy required to remove an electron from an isolated, gas
phase atom
electron affinity✔✔amount of energy released when a free, gas phase atom gains an electron
crystal lattice✔✔this forms when ionic compounds become solid; the ions are stabilized by
being surrounded by opposite charges. Also energy is released.
octet rule✔✔when atoms bond, they tend to gain, lose, or share electrons to result in eight
valence electrons
electronegativity✔✔the tendency of an atom in a molecule to attract electrons toward itself
polar covalent bond✔✔if two atoms of different electronegativity share electrons, this results
pure or nonpolar bond✔✔bond where electrons are equally shared
small electronegativity difference✔✔0-0.4
intermediate electronegativity difference✔✔0.4-2.0
large electronegativity difference✔✔2.0 +
, resonance structures✔✔lewis structures that differ only in the placement of electrons are
called what?
resonance hybrid✔✔combination of all possible resonance structures
endo✔✔is breaking bonds endo or exo
exo✔✔is forming bonds endo or exo
deltaH rxn from bond energies✔✔deltaH= SUM of energies broken - SUM of formed
hybridization✔✔when orbitals are close enough in energy, they can combine to form the same
number of new orbitals that are intermediate in energy
valence bond theory✔✔This theory states that atoms share valence electrons to form bonds.
Also, to comply with the octet rule, sometimes atoms need to hybridize to have enough
unpaired electrons.
gas kinetic molecular theory✔✔gases consist of many many particles that are really really small
and very far apart. The particles move in random straight lines that occasionally collide
pressure✔✔= force/area
units of pressure✔✔1 atm = 760 mmHg = 101 kPa
factors that affect pressure✔✔concentration, volume, and avg speed of particles
ANSWERS
ionization energy✔✔amount of energy required to remove an electron from an isolated, gas
phase atom
electron affinity✔✔amount of energy released when a free, gas phase atom gains an electron
crystal lattice✔✔this forms when ionic compounds become solid; the ions are stabilized by
being surrounded by opposite charges. Also energy is released.
octet rule✔✔when atoms bond, they tend to gain, lose, or share electrons to result in eight
valence electrons
electronegativity✔✔the tendency of an atom in a molecule to attract electrons toward itself
polar covalent bond✔✔if two atoms of different electronegativity share electrons, this results
pure or nonpolar bond✔✔bond where electrons are equally shared
small electronegativity difference✔✔0-0.4
intermediate electronegativity difference✔✔0.4-2.0
large electronegativity difference✔✔2.0 +
, resonance structures✔✔lewis structures that differ only in the placement of electrons are
called what?
resonance hybrid✔✔combination of all possible resonance structures
endo✔✔is breaking bonds endo or exo
exo✔✔is forming bonds endo or exo
deltaH rxn from bond energies✔✔deltaH= SUM of energies broken - SUM of formed
hybridization✔✔when orbitals are close enough in energy, they can combine to form the same
number of new orbitals that are intermediate in energy
valence bond theory✔✔This theory states that atoms share valence electrons to form bonds.
Also, to comply with the octet rule, sometimes atoms need to hybridize to have enough
unpaired electrons.
gas kinetic molecular theory✔✔gases consist of many many particles that are really really small
and very far apart. The particles move in random straight lines that occasionally collide
pressure✔✔= force/area
units of pressure✔✔1 atm = 760 mmHg = 101 kPa
factors that affect pressure✔✔concentration, volume, and avg speed of particles
